(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A car travels 76 m/s around a circular track with a 111 m radius.

The car's mass is 2500 kg, the track is angled at 21°, and the coefficient of friction is 0.18.

What is the magnitude of the resultant force on the car and driver, expressed as kN?

3. The attempt at a solution

Double-checking my work here to see if I'm understanding this correctly.

If:

Fk = µ*Fn

Fn = mg/cosΘ

Fc = mv²/r

Then:

Fc = 130090.09 N

Fk = 4723.75 N

Which leaves me with two questions: Is the above correct, and what am I leaving out of the forces before summing them?

editing this to add: I've gotten a series of formulas that produce the correct answer, but I do not know where they are derived from. If anyone could help explain this, I'd appreciate it.

1. [tex]A = \frac {m(v^2cos\theta - grsin\theta)}{r}[/tex]

2. [tex]B = \frac {mg + Asin\theta}{cos\theta}[/tex]

3. [tex](\mbox{Answer expressed in kN}) = \frac {Acos\theta + Bsin\theta}{1000}[/tex]

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# Homework Help: Circular motion with friction and banking - resultant forces

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